An Improved Wide Band Ocean Emissivity Radiative Transfer Model

A new microwave radiative transfer ocean surface emissivity model for horizontal and vertical polarizations has been developed. Ocean radiative transfer models find many applications in the remote sensing, and as such, it is important that they can accurately predict brightness temperatures (Tb) over a wide range of electromagnetic wavelengths, incidence angles and environmental conditions. This model calculates the ocean emissivity over frequencies (1 - 90 GHz), incidence angles (nadir - 75°) and the full dynamic range of observed ocean sea surface temperatures and salinity, and wind vector (speed and direction). This paper focuses on the evaluation of this CFRSL model using satellite microwave ocean brightness temperatures measured by the WindSat radiometer on the Coriolis satellite. One year of WindSat data have been collocated with the NOAA Global Data Assimilation System (GDAS) atmospheric profiles, which are used to translate the brightness temperature measurements at the top-of-the-atmosphere to the surface of the ocean. Comparisons between measured and modeled ocean surface brightness temperatures are presented over a range of sea surface temperatures and ocean wind speed for radiometer channels between 6 and 37 GHz. © 2010 IEEE